Financing Receivable And Off Balance Sheet Credit Loss Allowance

No definition available.

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Namespace Prefix:	ewbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Financing Receivable And Off Balance Sheet Credit Loss Allowance, Period Increase (Decrease)

+ References

No definition available.

+ Details

Name:	ewbc_FinancingReceivableAndOffBalanceSheetCreditLossAllowancePeriodIncreaseDecrease
Namespace Prefix:	ewbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reasonable and Supportable Forecast Period, Life Time Loss Rate, Period

+ References

No definition available.

+ Details

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Namespace Prefix:	ewbc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

+ Details

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Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ewbc_CommercialAndIndustrialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans Receivable and Allowance for Credit Losses - Allowance for Credit Losses Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) qtr	Dec. 31, 2023 USD ($)	Sep. 30, 2023 qtr	Jun. 30, 2023 qtr
Financing Receivable Allowance for Credit Losses
Life time loss rate, period span \| qtr	8
Allowance for credit losses \| $	$ 709	$ 706
Increase in allowance for credit losses \| $	$ 3
Commercial and industrial (“C&I”)
Financing Receivable Allowance for Credit Losses
Life time loss rate, period span \| qtr			8	11